Pilot study on the midsecond trimester examination of fetal nasal bone in the Chinese population.
D000293:Adolescent; D000328:Adult; D002681:China; D004314:Down Syndrome / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000196:embryology; D005260:Female; D006801:Humans; D016014:Linear Models; D009295:Nasal Bone / Q000000981:diagnostic imaging / Q000196:embryology*; D015588:Observer Variation; D010865:Pilot Projects; D011247:Pregnancy; D011256:Pregnancy Outcome; D011262:Pregnancy Trimester, Second; D012016:Reference Values; D015203:Reproducibility of Results; D016216:Ultrasonography, Prenatal